Climate and monthly weather forecastFlat Rock, IL
Climate and monthly weather forecast
Weather in January
January, the same as December, is a wintry winter month in Flat Rock, Illinois, with an average temperature fluctuating between 36.1°F (2.3°C) and 23.4°F (-4.8°C). January is the month when Flat Rock, Illinois, sees the lowest average temperatures, with a high of 36.1°F (2.3°C) and a low of 23.4°F (-4.8°C). Weather in January »Weather in February
The last month of the winter, February, is also an icy month in Flat Rock, Illinois, with temperature in the range of an average high of 41°F (5°C) and an average low of 27.1°F (-2.7°C). Flat Rock's entry into February measures an average high-temperature of a still icy 41°F (5°C), closely parallel to the preceding month. Weather in February »Weather in March
March, the first month of the spring in Flat Rock, is a fresh month, with temperature in the range of an average low of 36.7°F (2.6°C) and an average high of 53.1°F (11.7°C). Flat Rock's transition into March is marked by a temperature shift, moving from a cold 41°F (5°C) in February to a fresh 53.1°F (11.7°C). Weather in March »Weather in April
April in Flat Rock, Illinois, is a comfortable spring month, with an average temperature ranging between min 46.9°F (8.3°C) and max 64°F (17.8°C). Flat Rock's weather in April shows a rise in the average high-temperature, moving up from March's cool 53.1°F (11.7°C) to an enjoyable 64°F (17.8°C). Weather in April »Weather in May
May, the last month of the spring in Flat Rock, is a warm month, with an average temperature varying between 57.2°F (14°C) and 73.8°F (23.2°C). As April transitions into May, Flat Rock sees a rise in the average high-temperature, moving from a refreshing 64°F (17.8°C) to a moderately hot 73.8°F (23.2°C). Weather in May »Weather in June
June, the first month of the summer in Flat Rock, is also a moderately hot month, with an average temperature varying between 82°F (27.8°C) and 65.3°F (18.5°C). Flat Rock's weather in June shows a minor rise in the average high-temperature, moving slightly up from May's moderately hot 73.8°F (23.2°C) to a still warm 82°F (27.8°C). Weather in June »Weather in July
July, the same as June, is another warm summer month in Flat Rock, Illinois, with an average temperature fluctuating between 83.8°F (28.8°C) and 66.9°F (19.4°C). Flat Rock records the warmest temperatures in July, averaging a high of 83.8°F (28.8°C) and a low of 66.9°F (19.4°C). During July, the heat index is computed to be a hot 93.2°F (34°C). Weather in July »Weather in August
August, the last month of the summer in Flat Rock, is another warm month, with temperature in the range of an average high of 82.6°F (28.1°C) and an average low of 64.8°F (18.2°C). August's presence records an average high-temperature of a still warm 82.6°F (28.1°C), closely mirroring July's climate. Weather in August »Weather in September
The first month of the autumn, September, is still a warm month in Flat Rock, Illinois, with an average temperature ranging between min 59.5°F (15.3°C) and max 77.9°F (25.5°C). With the advent of September, Flat Rock experiences an average high-temperature of a still warm 77.9°F (25.5°C), mirroring a close resemblance to the previous month. Weather in September »Weather in October
October, like September, in Flat Rock, Illinois, is another refreshing autumn month, with an average temperature varying between 65.5°F (18.6°C) and 48.6°F (9.2°C). Flat Rock's October weather comes with a decrease in average high-temperatures, moving from a warm 77.9°F (25.5°C) in September to a comfortable 65.5°F (18.6°C). Weather in October »Weather in November
The last month of the autumn, November, is also a fresh month in Flat Rock, Illinois, with an average temperature fluctuating between 51.4°F (10.8°C) and 37.4°F (3°C). Arrival of November comes with a reduction in the average high-temperature, falling from a comfortable 65.5°F (18.6°C) in October to a cool 51.4°F (10.8°C). Weather in November »Weather in December
The first month of the winter, December, is still a cold month in Flat Rock, Illinois, with an average temperature varying between 41.2°F (5.1°C) and 29.8°F (-1.2°C). With December's onset, the average high-temperature recedes from November's fresh 51.4°F (10.8°C) to a cold 41.2°F (5.1°C). Weather in December »Updated: Aug 22, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Temperature records mark January as the coldest month, with highs averaging 36.1°F (2.3°C) and lows at 23.4°F (-4.8°C).
Throughout the year, there are 162.4 rainfall days, and 36.85" (936mm) of precipitation is accumulated.
January through April, November and December are months with snowfall.
January is the month with the most snowfall. Snow falls for 6.8 days and accumulates 2.32" (59mm) of snow.
Throughout the year, there are 22 snowfall days, and 7.64" (194mm) of snow is accumulated.
The month with the least sunshine is January, with an average of 4.2h of sunshine.
January, February, November and December, with an average maximum UV index of 2, are months with the lowest UV index.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, and the time zone changes from CST to CDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from CDT to CST.
April is the month with the most rainfall. Rain falls for 15.8 days and accumulates 5.2" (132mm) of precipitation.
In Flat Rock, snow does not fall in May through October.
With an average of 14h and 54min of daylight, June has the longest days of the year.
With an average of 10.3h of sunshine, June has the most sunshine of the year.
June through August, with an average maximum UV index of 6, are months with the highest UV index in Flat Rock.
The average temperatures reach their apex in July, averaging 83.8°F (28.8°C) at the high end and 66.9°F (19.4°C) at the low end.
The most humid month is July, with an average relative humidity of 81%.
The month with the least rainfall is September, when the rain falls for 12.6 days and typically collects 1.89" (48mm) of precipitation.
The least humid month is October, with an average relative humidity of 71%.
December has the shortest days of the year, with an average of 9h and 30min of daylight.
Average temperature
Flat Rock, IL
The warmest month (with the highest average high temperature) is July (83.8°F).
The month with the lowest average high temperature is January (36.1°F).
The month with the highest average low temperature is July (66.9°F).
The coldest month (with the lowest average low temperature) is January (23.4°F).
Average pressure
Flat Rock, IL
- Average pressure in January:
30.15"Hg - Average pressure in February:
30.11"Hg - Average pressure in March:
30.08"Hg - Average pressure in April:
29.95"Hg - Average pressure in May:
29.97"Hg - Average pressure in June:
29.93"Hg
- Average pressure in July:
29.98"Hg - Average pressure in August:
29.99"Hg - Average pressure in September:
30.03"Hg - Average pressure in October:
30.04"Hg - Average pressure in November:
30.14"Hg - Average pressure in December:
30.13"Hg
The month with the highest atmospheric pressure is January (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.93"Hg).
Average wind speed
Flat Rock, IL
- Average wind speed in January:
10mph - Average wind speed in February:
10mph - Average wind speed in March:
9.9mph - Average wind speed in April:
9.8mph - Average wind speed in May:
8.1mph - Average wind speed in June:
7.1mph
- Average wind speed in July:
5.9mph - Average wind speed in August:
5.9mph - Average wind speed in September:
6.7mph - Average wind speed in October:
8.5mph - Average wind speed in November:
9.1mph - Average wind speed in December:
9.1mph
The windiest months (with the highest average wind speed) are January and February (10mph).
The calmest months (with the lowest average wind speed) are July and August (5.9mph).
Average humidity
Flat Rock, IL
The month with the highest relative humidity is July (81%).
The month with the lowest relative humidity is October (71%).
Average rainfall
Flat Rock, IL
- Average rainfall in January:
2.56" - Average rainfall in February:
2.17" - Average rainfall in March:
2.8" - Average rainfall in April:
5.2" - Average rainfall in May:
3.98" - Average rainfall in June:
4.13"
- Average rainfall in July:
3.43" - Average rainfall in August:
2.76" - Average rainfall in September:
1.89" - Average rainfall in October:
2.56" - Average rainfall in November:
2.48" - Average rainfall in December:
2.91"
The wettest month (with the highest rainfall) is April (5.2").
The driest month (with the least rainfall) is September (1.89").
Average rainfall days
Flat Rock, IL
- Average rainfall days in January:
8.4 days - Average rainfall days in February:
9 days - Average rainfall days in March:
14.8 days - Average rainfall days in April:
15.8 days - Average rainfall days in May:
19.8 days - Average rainfall days in June:
17.2 days
- Average rainfall days in July:
18.8 days - Average rainfall days in August:
14.3 days - Average rainfall days in September:
12.6 days - Average rainfall days in October:
11.6 days - Average rainfall days in November:
10 days - Average rainfall days in December:
10.1 days
The month with the highest number of rainy days is May (19.8 days).
The month with the least rainy days is January (8.4 days).
Average snowfall
Flat Rock, IL
The month with the highest snowfall is January (2.32").
The months with the least snowfall are May, June, July, August, September and October (0").
Average snowfall days
Flat Rock, IL
- Average snowfall days in January:
6.8 days - Average snowfall days in February:
5.8 days - Average snowfall days in March:
2.6 days - Average snowfall days in April:
0.3 days - Average snowfall days in May:
0 days - Average snowfall days in June:
0 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0 days - Average snowfall days in October:
0 days - Average snowfall days in November:
1.8 days - Average snowfall days in December:
4.7 days
The month with the highest number of snowfall days is January (6.8 days).
The months with the least snowfall days are May, June, July, August, September and October (0 days).
Average daylight / Average sunshine
Flat Rock, IL
- Average daylight in January:
9h and 48min - Average daylight in February:
10h and 48min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 12min - Average daylight in May:
14h and 18min - Average daylight in June:
14h and 54min
- Average daylight in July:
14h and 36min - Average daylight in August:
13h and 36min - Average daylight in September:
12h and 24min - Average daylight in October:
11h and 12min - Average daylight in November:
10h and 6min - Average daylight in December:
9h and 30min
The month with the longest days is June (Average daylight: 14h and 54min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in January:
4h and 12min - Average sunshine in February:
4h and 18min - Average sunshine in March:
6h and 12min - Average sunshine in April:
8h and 0min - Average sunshine in May:
8h and 42min - Average sunshine in June:
10h and 18min
- Average sunshine in July:
10h and 6min - Average sunshine in August:
10h and 6min - Average sunshine in September:
8h and 54min - Average sunshine in October:
6h and 36min - Average sunshine in November:
5h and 18min - Average sunshine in December:
4h and 24min
The month with the most sunshine is June (Average sunshine: 10h and 18min).
The month with the least sunshine is January (Average sunshine: 4h and 12min).
Average sunshine days
Flat Rock, IL
- Average sunshine days in January:
16.3 days - Average sunshine days in February:
13.6 days - Average sunshine days in March:
13.8 days - Average sunshine days in April:
12 days - Average sunshine days in May:
9.7 days - Average sunshine days in June:
10 days
- Average sunshine days in July:
9.8 days - Average sunshine days in August:
14.1 days - Average sunshine days in September:
15.1 days - Average sunshine days in October:
17.9 days - Average sunshine days in November:
18 days - Average sunshine days in December:
16.5 days
The month with the most sunshine days is November (18 days).
The month with the least sunshine days is May (9.7 days).
Average UV index
Flat Rock, IL
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 2).
Average cloud cover
Flat Rock, IL
The month with the most cloud cover is January (Cloud cover 55).
The month with the least cloud cover is August (Cloud cover 29).
Average visibility
Flat Rock, IL
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
